C# 按下该键时执行该操作

我正在处理我的项目，我需要添加一个只在按下左CTRL键时执行的操作

这是我的代码：

   private void Izrada_kartice_KeyDown(object sender,KeyEventArgs e)
    {

        if(e.Control)
        {
            promijeni_veličinu_naslov = true;

            this.BackColor = Color.Red;
        }

    }

    private void Izrada_kartice_KeyUp(object sender, KeyEventArgs e)
    {
        if (e.Control)
        {
            promijeni_veličinu_naslov = false;

            this.BackColor = Color.Green;
        }
    }

现在，当我运行此代码并按CTRL键时，一切都正常，但当我释放CTRL键时 什么也没发生

我想试试这个：

     private void Izrada_kartice_KeyDown(object sender,KeyEventArgs e)
{

    if(e.KeyCode == Keys.A)
    {
        promijeni_veličinu_naslov = true;

        this.BackColor = Color.Red;
    }

}

private void Izrada_kartice_KeyUp(object sender, KeyEventArgs e)
{
        if(e.KeyCode == Keys.A)
    {
        promijeni_veličinu_naslov = false;

        this.BackColor = Color.Green;
    }
}

---

这可以正常工作，但我需要使用CTRL键来执行此操作，释放CTRL键时会触发KeyUp事件，但由于不再按住CTRL键，

e.Control

布尔值未设置为True

简而言之：不要通过检查

e.Control

来检测Ctrl的释放，而是检查

e.KeyCode

；它将是

键。ControlKey

if(e.KeyCode == Keys.ControlKey)
{
    ...
}

---

在第二个代码中，将Keys.A替换为Keys.ControlKey，如下所示：

private void Izrada_kartice_KeyDown(object 
sender,KeyEventArgs e)
{

if(e.KeyCode == Keys.ControlKey)
{
    promijeni_veličinu_naslov = true;

    this.BackColor = Color.Red;
}

}

private void Izrada_kartice_KeyUp(object sender, 
KeyEventArgs e)
{
    if(e.KeyCode == Keys.ControlKey)
{
    promijeni_veličinu_naslov = false;

    this.BackColor = Color.Green;
}
}